Buttonhole cutting mechanism



Feb. 23, 1932. J. KIEWICZ BUTTONHOLE CUTTING MECHANISM Filed Aug. 21, 1929 3 Sheets-Sheet r lnvenTon,

dohn Kiewicg WW Anya;

Feb. 23, 1932.

J. Klawlci BUTTONHOLE CUTTING MECHANISM Filed Aug. 21, 1929 3 $heets-5heet 2 lnven for. Uohn Kiewicg b a wa MyW Anya.

Feb. 23, 1932. J. KIEWICZ BUTTONHOLE CUTTING MECHANISM Fil ed Aug. 21, 1929 3 Sheets-Sheet 3 lnvenTor.

LJohn Kiewicg Afl'ys.

Patented Feb. 23, 1932 UNITED STATES PATENT OFFICE JOHN KIEWICZ, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE REECE BUTTON HOLE MACHINE COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE BUTTONHOLE CU'I'TTNG MECHANISM Application filed August 21, 1929. Serial. No. 387,296.

This invention relates to buttonhole sewing machines and particularly to means for cutting the buttonhole.

The features wherein the invention resides 5 will be more particularly hereinafter set forth and then pointed out in the claims.

In order to give an understanding of the invention I have illustrated in the drawings selected embodiment thereof which will now be described after which the novel features will be pointed out in the appended claims.

Fig. 1 is a side view of a sewing machine embodying my invention with parts broken out;

Fig. 2 is a plan view of the work-supporting portion of the bed with the clamp plates removed to better show the turret and part of the buttonhole-cutting mechanism;

Fig. 3 is a fragmentary view showing the buttonhole cutters in operative position;

Fig. i is a plan view similar to Fig. 2 but illustrating the buttonhole cutter in advance position;

Fig. 5 is a section on the line 55, Fig. 4;

Fig. 6 is a section on the line 66, Fig. 3.

In the drawings 1 indicates the frame of the sewing machine which carries the stitchforming mechanism, the latter comprising the upper needle 2 mounted in the vertically-reciprocating needle bar 3 and operating from above the work, and underthread mechanism situated beneath the work.

The frame 1 is mounted on the bed 31 which carries the work clamps 46 by which 35 the work is clamped in position. The stitchforming mechanism and the work clamps have a relative movement during the sewing on the buttonhole as usual in buttonhole sewing machines and in this construction this relative movement is secured by reason of the fact that the frame 1 is mounted to move back and forth on the bed 31. As usual in buttonhole sewing machines of this type the movement of the frame 1 on the bed 31 includes a movement of the frame to carry the parts from buttonhole-cutting to stitching position andvice versa and also a feeding movement during the stitching along the sides of the buttonhole. As is well known to those familiar with this type of buttonhole sewing machine the machine will come to rest at the end of a sewing operation with the frame 1 in buttonhole-cutting position and when the machine is started in operation the frame is moved from buttonhole-cutting to stitching position and then the stitchforming mechanism is set in operation and the stitching along the sides of the buttonhole proceeds. After the stitching is completed the frame 1 has another movement carrying the parts into buttonhole-cutting position, in which position the machine finally comes to rest.

As stated above, the sewing machine herein shown is of that type in which the stitchforming mechanism is mounted to rotate at each end of the buttonhole and for this purpose the under-thread mechanism is mounted on the usual turret 5 which carries at its upperend the throat plate 6 having the sewing opening through which the upper needle operates, said turret being mounted to rotate in suitable bearings 8. The needle bar 3 with the needle 2 is also mounted to rotate and the means herein shown for giving the turret and the needle bar their rotational movements at each end of the buttonhole is such as is commonly employed in buttonhole sewing machines.

This rotational movement is secured from a vertically-arranged rock shaft 9 journalled in the frame and carrying at its upper end a segmental gear 10 meshing with a gear 11 by which. the needle bar is turned, said shaft carrying at its lower end another segmental gear which meshes with a gear on theturret 5 as usual in buttonhole sewing machines. The turning movement of the rock shaft 9 is secured at proper times from the main cam 14 by any usual means employed for this purpose.

The buttonhole-cutting mechanism comprises two cutting elements 20 and 21, one of which is a cutting blade and the other of which is a cutting block. The element 20 is shown as mounted on a lever 22 pivoted to the frame at 23 and having at its rear end a follower 24 adapted to be engaged by a cam projection 25 on the main cam 14, said cam projection being so disposed that at the proper time in the sewing cycle the lever 22 will be actuated to bring the cutting ele- 1116111320 into operative position. v The other cutting element 21 is movably mounted, it normally being in its retracted position shown in Fig. 1 during the sewing on the buttonhole but being moved forward into its operative position shown in Fig. 3 at the time that the lever 22 is actuated.

Either cutting element may be the cutting blade and the other the cutting block. In the construction shown the member 20 is in the form of a block and the member 21 has the cutting edge but so far as the invention is concerned the member 20 may have the cutting edge and the member 21 might be in the form of a block. j

The cutting member 21'is carried by a block 26 which is adjustably carried by a slide 27 that slides back and forth in ways 28 formed on the cam casing 15. The block 26 is retained in its adjusted position on the slide 27 through the medium of clamping screws 29.

As stated above the cutting element 21 and the block 26 on which it is mounted are normally in retracted position shown in Figs. 1 and 2 but they are moved forward into the operative position shown in Figs. 3 and 4 by the operative movement of the lever 22.

This is accomplished by the following mechanism. slidably mounted in bearings 30 carried by the stationary bed 31 of the machine is a controlling rod 32, the latter having an arm 33 fast thereto, the end 34 of which extends into an opening formed in the side of. the block 26. This rod 32 is provided with a notch 35 in which is received the lower end of a lever 36, the latter being pivoted at 37 to a bracket 38 on the frame 1. This lever is provided with a cam surface 39 adapted to be engaged by a roller 40 on the end of a lever 41 pivoted at 42 to the frame, said lever having at its rear end a lateral projection '43 adapted to be engaged by the-rear end of the lever 22. The lever 41 is actedon by a spring 44 which tends to hold it in the position shown in Fig. 1 and the lever 36 is acted on by a return spring 45. j c

When the lever 22 is actuated to bring the cutting element 20 into operative position the upward movementof the rear end of the lever will rock the lever 41 thereby causing the roll 40 to engage the cam surface 39 and swing the lever 36 forwardly into the position shown in Fig. 3. Such movement of the lever will carry the rod 32 forwardly thereby moving the slide 27 forwardly and placing the cutting element 21 in its operative position shown in Fig. 3. Hence, as the cutting element 20 moves downwardly the co-operating element 21 will move forwardly into position beneath the element 20 and the two elements will serve to cut the buttonhole slit in the work which is then held in place by the work clamps 46.

When the cam 25 passes out from under the follower 24 the lever 22 will be restored to its raised inoperative position and the sprmgs 44 and 45 will return the levers 41 and 36110 their normal position, such movement of the lever 36 operating through the rod 32 to retract the cutting element 21 into its inoperative position.

I claim: 1. In a buttonhole sewing machine, the combination with stitch-forming mechanism,

of buttonhole-cutting mechanism comprising two co-operating cutting members, a lever on which one of the members is mounted, a horizontally-movable slide on which the other member is mounted, movement of the slide carrying the other member into and out of operative position, means to rock the lever to move the cutting member carried thereby into and out of operative position, and means actuated by said lever to give the slide a movement to carry the other cutting member into operative position.

2. In a buttonhole sewing machine, the combination with a frame. of a lever pivoted to said frame, a buttonhole cutting member carried by the lever, a slide movable horizontally on the frame, a second cutting member carried by said slide, said slide normally being in retracted position with its cutting member out of register with the other cutting member, means to give the lever its operative movement, and means actuated by said lever to movethe slide forwardly thereby to bring the cutting member carried thereby into register with the cutting member carried by the lever.

3. In a buttonhole-sewing machine, the

combination with a bed member, of a frame mounted thereon for movement longitudinally thereof, stitch-forming mechanism carried by the frame, buttonhole-cutting mechanism comprising two co-operating cutting members, a lever pivotally mounted on the frame and on which'one of the cutting members is carried, a slide mounted on the frame for horizontal sliding movement into and out of operative position and on which the other member is carried, and means to move the slide relative to the frame into and out'of its operative position.

4. In a buttonhole-sewing machine, the combination with stitch-forming mechanism,

of buttonhole-cutting mechanism comprising two co-operating cutting members, a lever on which one of the members is mounted a horizontally-movable slide on which the other member is mounted, movement of the slide carrying said other member into and out of operative position in which it registers with the first-named cutting member, a spring normally holding said slide in its inoperative position, means to rock the lever and means actuated by the lever to move the slide into its operative position.

' In testimony whereof, I have signed my name to this specification.

JOHN KIEWICZ. 

